Continuous surveillance of pathogens detects excretion of avian orthoreovirus and parvovirus by several wild waterfowl: possible wild bird reservoirs.

Migratory wild birds can carry various pathogens, such as influenza A virus, which can spread to globally and cause disease outbreaks and epidemics. Continuous epidemiological surveillance of migratory wild birds is of great significance for the early warning, prevention, and control of epidemics. To investigate the pathogen infection status of migratory wild birds in eastern China, fecal samples were collected from wetlands to conduct pathogen surveillance. The results showed that duck orthoreovirus (DRV) and goose parvovirus (GPV) nucleic acid were detected positive in the fecal samples collected from wild ducks, egrets, and swan. Phylogenetic analysis of the amplified viral genes reveals that the isolates were closely related to the prevalent strains in the regions involved in East Asian-Australasian (EAA) migratory flyway. Phylogenetic analysis of the amplified viral genes confirmed that they were closely related to circulating strains in the regions involved in the EAA migration pathway. The findings of this study have expanded the host range of the orthoreovirus and parvovirus, and revealed possible virus transmission between wild migratory birds and poultry.

Genome analysis of gyroviruses identified in waterfowl in Arizona (USA).

Gyroviruses are small single-stranded DNA (ssDNA) viruses that are largely associated with birds. Chicken anemia virus is the most extensively studied gyrovirus due to its disease impact on the poultry industry. However, we know much less about gyroviruses infecting other avian species. To investigate gyroviruses infecting waterfowl, we determined six complete genome sequences that fall into three gyrovirus groups, referred to as waterfowl gyrovirus 1 (n = 3), 2 (n = 2), and 3 (n = 1), in organs from hunter-harvested waterfowl from Arizona (USA). The waterfowl gyrovirus 1 variants were identified in multiple organs of a single American wigeon and represent a tentative new species. The waterfowl gyrovirus 2 variants were identified in the livers of two American wigeons and share >70% VP1 nucleotide sequence identity with gyrovirus 9, previously identified in the spleen of a Brazilian Pekin duck (MT318123) and a human fecal sample (KP742975). Waterfowl gyrovirus 3 was identified in a northern pintail spleen sample, and it shares >73% VP1 nucleotide sequence identity with two gyrovirus 13 sequences previously identified in Brazilian Pekin duck spleens (MT318125 and MT318127). These gyroviruses are the first to be identified in waterfowl in North America, as well as in American wigeons and northern pintails.

Avipoxvirus detected in tumor-like lesions in a white-faced whistling duck (Dendrocygna viduata) / Avipoxvirus detectado em lesões tipo tumorais em uma marreca-irerê (Dendrocygna viduata)

Avipoxvirus is the etiological agent of the avian pox, a well-known disease of captive and wild birds, and it has been associated with tumor-like lesions in some avian species. A white-faced whistling duck (Dendrocygna viduata) raised in captivity was referred to a Veterinary Teaching Hospital in Northeast due to cutaneous nodules present in both wings. A few days after the clinical examination, the animal died naturally. Once submitted to necropsy, histopathological evaluation of the lesions revealed clusters of proliferating epithelial cells expanding toward the dermis. Some of these cells had round, well-defined, intracytoplasmic eosinophilic material suggestive of poxvirus inclusion (Bollinger bodies). PCR performed on the DNA extracted from tissue samples amplified a fragment of the 4b core protein gene (fpv167), which was purified and sequenced. This fragment of Avipoxvirus DNA present in these tumor-like lesions showed high genetic homology (100.0%) with other poxviruses detected in different avian species in several countries, but none of them were related to tumor-like lesions or squamous cell carcinoma. This is the first report of Avipoxvirus detected in tumor-like lesions of a white-faced whistling duck with phylogenetic analysis of the virus.(AU)

Avipoxvirus é o agente etiológico da varíola (bouba) aviária, uma doença bem descrita em aves de cativeiro e selvagens, tendo sido associada a lesões semelhantes a tumores em algumas dessas espécies. Uma marreca piadeira (Dendrocygna viduata), criada em cativeiro, foi atendida em um Hospital Veterinário na região nordeste devido à presença de nódulos cutâneos em ambas as asas. Alguns dias após o exame clínico, o animal veio a óbito naturalmente. A ave foi submetida à necropsia e coletados fragmentos das lesões para análise histopatológica, que revelou proliferação de células epiteliais expandindo para a derme. Algumas dessas células possuíam material eosinofílico intracitoplasmático e bem definido, sugestivo de inclusão de poxvírus (corpúsculos de Bollinger). A PCR realizada a partir do DNA extraído de amostras das lesões amplificou um fragmento do gene da proteína do núcleo 4b (fpv 167), que foi purificado e sequenciado. Esse fragmento de DNA de Avipoxvirus presente nas lesões relevou alta homologia genética (100,0%) com outros poxvírus detectados em diferentes espécies de aves em vários países, mas nenhum deles estava relacionado a lesões tumorais ou carcinoma espinocelular. Este é o primeiro relato de Avipoxvirus detectado em lesões semelhantes a tumores em uma marreca piadeira com caracterização molecular do vírus.(AU)

Detection of avian metapneumovirus subtype A from wild birds in the State of São Paulo, Brazil / Detecção de metapneumovirus aviário subtipo A em aves silvestres no estado de São Paulo, Brasil

The present study investigated the circulation of avian metapneumovirus (aMPV) in wild birds in Brazil. To do so, 131 samples from 366 oropharyngeal or cloacal swabs collected from 18 species of birds were tested individually or in pools by RT-PCR. Samples detected by RT-PCR were selected for DNA sequencing. Thirteen (9.9%) samples were detected by the RT-PCR targeting the N gene and four out of 13 samples were sequenced. Sequencing results showed a high identity with the aMPV subtype A. Our results confirm the circulation of the aMPV subtype A in wild birds in Brazil even five years after its last detection.(AU)

O presente estudo investigou a circulação de metapneumovírus aviário em aves silvestres no Brasil. Para tanto, 131 amostras de 366 suabes orofaringeanos ou cloacais coletados de 18 espécies de aves foram testadas individualmente ou na forma de pools por RT-PCR. As amostras detectadas por RT-PCR foram selecionadas para sequenciamento. Treze (9,9%) das amostras foram detectadas por RT-PCR tendo o gene N como alvo; destas, quatro foram sequenciadas com sucesso. Resultados do sequenciamento mostraram alta identidade com o aMPV de subtipo A. Nossos resultados confirmam a circulação de aMPV subtipo A em aves silvestres no Brasil mesmo cinco anos após sua última detecção.(AU)